So disease-causing bacteria in the body finally have multiplied to the point where their numbers are large enough to cause illness. What’s next? They get out their “smart phones” and whisper “Let’s roll!” That’s how an article in ACS’ monthly Chemical Reviews describes the substances — “smart phones of the microbial world” — that bacteria use to transmit chemical signals that launch infections and monitor their environment. The authors describe progress toward understanding and blocking this biochemical chitchat, a development that could lead to new treatments for the growing problem of antibiotic-resistant infections.

Marvin Whiteley and Holly Huse point out that bacteria use chemical signals to communicate with each other. These signals can trigger infections when their numbers reach a certain threshold — a process known as “quorum sensing.” Scientists around the world are trying to find potential new drugs that garble or block those signals, and in doing so, fight infection. One prime target are the 4-quinolones, signaling molecules produced by Pseudomonas aeruginosa, a common disease-causing microbe.

Their review of more than 60 years of research on 4-quinolones found promising indications that such a conversation-stopper will be developed. Scientists, for instance, now have evidence that a certain enzyme that modifies 4-quinolones can reduce infection. “These results are encouraging for the development of new therapeutics that target 4-quinolone signaling,” the article noted.